So the solutions are: SharpDX, ANX, or SharpDX Toolkit. Correct?
Is your app a game that relies on Microsoft XNA components for graphics rendering? If so, you cannot use XNA with a Windows 8 application. You also cannot effectively use DirectX with managed code; you must develop the DirectX game with C++, unless you use a third party managed API. For more info, see Creating a DirectX game.